# US 8,751,127 B2 · Position estimation system and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,751,127 B2 - Document ID: US8751127B2 - Status: Granted - Kind: B2 - Application number: 13/307,707 - Filed: 2011-11-30 - Published: 2013-05-30 - Granted: 2014-06-10 - Earliest claimed: 2011-11-30 - Assignees: General Electric Company - Applicants: Harri Viittala; Simone Soderi; Jani Saloranta; Matti Hämäläinen; Jari Iinatti - Inventors: Harri Viittala; Simone Soderi; Jani Saloranta; Matti Hämäläinen; Jari Iinatti - Web page: https://patentgrep.com/patent/US8751127B2 ## CPC - G01S 5/0263: {by combining or switching between positions derived from two or more separate positioning systems} - B61L 15/0027: {Radio-based, e.g. using GSM-R} - B61L 25/025: {Absolute localisation, e.g. providing geodetic coordinates} - B61L 25/026: {Relative localisation, e.g. using odometer} - G01S 13/74: Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems - G01S 13/876: {Combination of several spaced transponders or reflectors of known location for determining the position of a receiver (G01S13/874 takes precedence)} - B61L 3/125: {using short-range radio transmission} - G01S 2013/466: {by Trilateration, i.e. two antennas or two sensors determine separately the distance to a target, whereby with the knowledge of the baseline length, i.e. the distance between the antennas or sensors, the position data of the target is determined} - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - B61L: GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC (brakes or auxiliary equipment B61H, B61K; point or crossing construction E01B) ## Abstract There is provided a vehicle with the capability of estimating its position. An exemplary vehicle comprises a positioning unit configured to operate in a first mode for communicating with one or more first radio-responsive devices and operate in a second mode for communicating with one or more second radio responsive devices. The positioning unit is configured to estimate a coarse position of the vehicle based on data received from the first transceiver, and estimate a fine position of the vehicle based on data received from the second transceiver. ## Claims ### Claim 1 A vehicle, comprising: a positioning unit configured to operate in a first mode for communicating with one or more first radio-responsive devices and operate in a second mode for communicating with one or more second radio-responsive devices; wherein the positioning unit is configured to estimate a coarse position of the vehicle based on data received while operating in the first mode, and estimate a fine position of the vehicle based on data received while operating in the second mode; and wherein the positioning unit is configured to estimate at least one of the fine position or the coarse position by transmitting an outbound signal to the one or more first radio-responsive devices or to the one or more second radio-responsive devices, respectively, receiving a return signal corresponding to the outbound signal from the one or more first radio-responsive devices or the one or more second radio-responsive devices, and measuring the time difference between the transmission of the outbound signal and the receiving of the return signal. ### Claim 2 (depends on 1) The vehicle of claim 1, wherein the positioning unit comprises: a first transceiver for operating in the first mode, the first transceiver configured to communicate with the one or more first radio-responsive devices; and a second transceiver for operating in the second mode, the second transceiver configured to communicate with the one or more second radio-responsive devices. ### Claim 3 (depends on 1) The vehicle of claim 1, wherein: while in the first mode, the positioning unit communicates with the one or more first radio-responsive devices using a first signal with a first bandwidth; and while in the second mode, the positioning unit communicates with the one or more second radio-responsive devices using a second signal with a second bandwidth larger than the first bandwidth. ### Claim 4 (depends on 3) The vehicle of claim 3, wherein the first bandwidth is approximately 5 to 40 Megahertz and the second bandwidth is approximately 500 Megahertz to 2 Gigahertz. ### Claim 5 (depends on 1) The vehicle of claim 1, wherein: while in the first mode, the positioning unit communicates with the one or more first radio-responsive devices using an IEEE 802.11 protocol; and while in the second mode, the positioning unit communicates with the one or more second radio-responsive devices using Ultra-Wideband (UWB) pulses. ### Claim 6 (depends on 1) The vehicle of claim 1, wherein: the positioning unit is configured to operate in the first mode for communicating with the one or more first radio-responsive devices, said one or more first radio-responsive devices comprising a first set of stationary radio-responsive devices disposed relative to a point of interest, and wherein the positioning unit is configured to operate in the second mode for communicating with the one or more second radio-responsive devices, said one or more second radio-responsive devices comprising three or more reflectors disposed at known locations relative to the point of interest, said reflectors being at least one of active or passive reflectors; and the positioning unit is configured to estimate the fine position based on the time difference between the transmission of the outbound signal and the receiving of the return signal reflected from at least one of three or more reflectors. ### Claim 7 A vehicle comprising: a positioning unit configured to operate in a first mode for communicating with one or more first radio-responsive devices and operate in a second mode for communicating with one or more second radio responsive devices, wherein the positioning unit is configured to estimate a coarse position of the vehicle based on data received while operating in the first mode, and estimate a fine position of the vehicle based on data received while operating in the second mode; and a control unit coupled to the positioning unit and a braking system configured to receive a braking control signal from a control unit, wherein: within a coarse area of interest, the braking control signal is based on the coarse position of the vehicle; and within a fine area of interest the braking control signal is based on the fine position of the vehicle. ### Claim 8 A system for estimating position, comprising: a first set of stationary radio-responsive devices disposed relative to a point of interest, the point of interest comprising a docking station, a re-fueling station, or a passenger platform; a second set of stationary radio-responsive devices disposed relative to the point of interest; and a vehicle comprising: a positioning unit configured to operate in a first mode for communicating with the first set of radio-responsive devices and operate in a second mode for communicating with the second set of radio responsive devices; wherein the positioning unit is configured to estimate a coarse position of the vehicle based on data received while operating in the first mode, and estimate a fine position of the vehicle based on data received while operating in the second mode, and wherein the positioning unit is configured to estimate at least one of the coarse position or the fine position based on a measured time-of-flight of signals sent to and received from the first set of radio-responsive devices or the second set of radio-responsive devices, respectively. ### Claim 9 (depends on 8) The system of claim 8, wherein the positioning unit comprises: a first transceiver for operating in the first mode, the first transceiver configured to communicate with the first set of radio-responsive devices; and a second transceiver for operating in the second mode, the second transceiver configured to communicate with the second set radio-responsive devices. ### Claim 10 (depends on 9) The system of claim 9, wherein the first transceiver communicates with the first set of radio-responsive devices using a first signal with a first bandwidth, the second transceiver communicates with the second set of radio-responsive devices using a second signal with a second bandwidth, and the second bandwidth is larger than the first bandwidth. ### Claim 11 (depends on 10) The system of claim 10, wherein the first bandwidth is approximately 5 to 40 Megahertz and the second bandwidth is approximately 500 Megahertz to 2 Gigahertz. ### Claim 12 (depends on 10) The system of claim 10, wherein the first transceiver is an IEEE 802.11 protocol transceiver and the second transceiver is an Ultra-Wideband (UWB) transceiver. ### Claim 13 (depends on 8) The system of claim 8, wherein each radio-responsive device in the first set of radio-responsive devices comprises a wireless communication device configured to receive an outbound signal transmitted from the positioning unit, generate a return signal, and transmit the return signal, wherein the outbound signal and the return signal comprise the signals for which the time-of-flight is measured. ### Claim 14 (depends on 13) The system of claim 13, wherein the positioning unit and the wireless communication device communicate using an IEEE 802.11 standard protocol. ### Claim 15 (depends on 8) The system of claim 8, wherein each radio-responsive device in the second set of radio-responsive devices is an active reflector. ### Claim 16 A system for estimating position, comprising: a first set of stationary radio-responsive devices disposed relative to a point of interest; a second set of stationary radio-responsive devices disposed relative to the point of interest; and a vehicle comprising: a positioning unit configured to operate in a first mode for communicating with the first set of radio-responsive devices and operate in a second mode for communicating with the second set radio responsive devices; wherein the positioning unit is configured to estimate a coarse position of the vehicle based on data received while operating in the first mode, and estimate a fine position of the vehicle based on data received while operating in the second mode; wherein the second set of radio-responsive devices comprises three or more active reflectors disposed at known locations relative to the point of interest, and estimating the fine position comprises measuring a time-of-flight of signals sent to and reflected from the three or more active reflectors. ### Claim 17 A method of estimating position, comprising: within a first area of interest, communicating with one or more first radio responsive devices to estimate a coarse position; within a second area of interest, communicating with one or more second radio-responsive devices to estimate a fine position; and transmitting a braking signal to a braking system, wherein: within the first area of interest, the braking signal is generated based on the coarse position; and within the second area of interest, the braking signal is based on the fine position. ### Claim 18 (depends on 17) The method of claim 17, wherein communicating with one or more first radio-responsive devices comprises transmitting an outbound signal using an IEEE 802.11 protocol and receiving an inbound signal transmitted by the one or more first radio responsive devices using the IEEE 802.11 protocol. ### Claim 19 (depends on 17) The method of claim 17, wherein communicating with one or more second radio-responsive devices comprises transmitting Ultra-wideband (UWB) pulses and receiving corresponding echoes reflected from the one or more second radio-responsive devices. ### Claim 20 (depends on 17) The method of claim 17, wherein communicating with the first radio-responsive device uses a first bandwidth, and communicating with the second radio-responsive device uses a second bandwidth larger than the first bandwidth. ### Claim 21 (depends on 20) The method of claim 20, wherein the first bandwidth is approximately 5 to 40 Megahertz and the second bandwidth is approximately 500 Megahertz to 2 Gigahertz. ### Claim 22 A positioning system, comprising: a positioning unit configured to operate in a first mode for communicating with one or more first radio-responsive devices and operate in a second mode for communicating with one or more second radio-responsive devices; wherein the positioning unit is configured to estimate a coarse position of a vehicle in which the positioning unit is disposed based on data received while operating in the first mode, and estimate a fine position of the vehicle based on data received while operating in the second mode, and wherein the positioning unit is configured to estimate at least one of the coarse position or the fine position based on a measured time-of-flight of signals sent to and received from the first radio-responsive devices or the second radio-responsive devices, respectively. ### Claim 23 (depends on 22) The positioning system of claim 22, wherein: the positioning unit is configured to operate in the first mode for communicating with the one or more first radio-responsive devices, said one or more first radio-responsive devices comprising a first set of stationary radio-responsive devices disposed relative to a point of interest, and wherein the positioning unit is configured to operate in the second mode for communicating with the one or more second radio-responsive devices, said one or more second radio-responsive devices comprising three or more reflectors disposed at known locations relative to the point of interest, said reflectors being at least one of active or passive reflectors; and the positioning unit is configured to estimate the fine position based on the measured time-of-flight of the signals sent to and reflected from the three or more reflectors.